Additional spring and follower mechanism built into valve cover or bearing bridge

Abstract

A torque pulsated variable cam timing camshaft arrangement for a reciprocating piston, internal combustion engine is provided. The arrangement includes a sprocket. A torque pulsated phaser unit is operatively associated with the sprocket. A camshaft is operatively associated with the sprocket and the camshaft torsionally powers the phaser unit. The camshaft has a cam lobe engaged with a first cam follower for controlling a position of a spring biased valve. A spring biased second cam follower is engaged with the cam lobe providing a torsional input to the camshaft.

What is claimed is: 
     
       1. A reciprocating piston internal combustion engine torque pulse VCT camshaft arrangement comprising:
 a sprocket; 
 a cam torque actuated phaser connected with said sprocket; 
 a camshaft connected with said sprocket and torsionally powering said cam torque actuated phaser; 
 a cam lobe connected with said camshaft being engaged with a first cam follower for controlling a position of a valve biased by a first spring; and 
 a second cam follower biased by a contacting spring separate from said first spring biasing said valve, said second cam follower being engaged with said cam lobe for imparting a torsional input to said camshaft. 
 
     
     
       2. A camshaft arrangement as described in  claim 1  wherein said first cam follower is a rocker arm type cam follower. 
     
     
       3. A camshaft arrangement as described in  claim 1  wherein said second cam follower is a rocker type cam follower. 
     
     
       4. A camshaft arrangement as described in  claim 1  wherein said second cam follower is connected on a bearing bridge. 
     
     
       5. A camshaft arrangement as described in  claim 1  wherein said second cam follower is connected on a valve cover. 
     
     
       6. A camshaft arrangement as described in  claim 1  wherein said first and second cam followers translate along an axis aligned with one another. 
     
     
       7. A camshaft arrangement as described in  claim 1  wherein said first and second cam followers translate along an axis at an angle with respect to one another. 
     
     
       8. A camshaft arrangement as described in  claim 1  wherein said camshaft is a concentric camshaft arrangement having a first camshaft angularly adjustable with respect to said sprocket and a second concentric camshaft. 
     
     
       9. A camshaft arrangement as described in  claim 8  wherein said first camshaft is positioned within said second camshaft and said second camshaft is torsionally fixably connected with said sprocket. 
     
     
       10. A camshaft arrangement as described in  claim 8  having one said camshaft with lobes to open a valve and said other camshaft with lobes to close said same valve. 
     
     
       11. A camshaft arrangement as described in  claim 8  having one camshaft with lobes for an exhaust valve and said other camshaft with lobes for an intake valve. 
     
     
       12. A camshaft arrangement as described in  claim 11  wherein said second cam follower is engaged with a lobe for an intake valve. 
     
     
       13. A camshaft arrangement as described in  claim 1  wherein said sprocket is powered by a flexible tensioned torsional force transfer member engaged with a sprocket connected with a crankshaft of an engine. 
     
     
       14. A reciprocating piston internal combustion engine torque pulse VCT camshaft arrangement comprising:
 a sprocket; 
 a cam torque actuated phaser connected with said sprocket; 
 a first camshaft connected with said sprocket and torsionally powering said cam torque actuated phaser, said first camshaft having a plurality of lobes for opening and closing exhaust valves; 
 a second camshaft angularly adjustable with respect to said first camshaft via said cam torque actuated phaser and being concentric with respect to said first camshaft, said second camshaft having cam lobes for opening and closing intake valves, said intake valves being biased by a respective first spring; 
 a first cam follower engaged with at least one of said second camshaft cam lobes for controlling a position of one of said intake valves; and 
 a second cam follower biased by a contacting spring separate from said respective first spring biasing said intake valves, second cam follower being engaged with at least one of said cam lobes engaged with said first cam follower for imparting torsional input to said second camshaft. 
 
     
     
       15. A torque pulse VCT camshaft arrangement comprising:
 a sprocket; 
 a cam torque actuated phaser connected with said sprocket; 
 a first camshaft connected with said sprocket and torsionally powering said camshaft phaser, said first camshaft having a plurality of lobes for controlling a closing position of valves biased by respective first springs; 
 a second camshaft angularly adjustable with respect to said first camshaft via said cam torque actuated phaser and being concentric with respect to said first camshaft, said second camshaft having a plurality of lobes for controlling an opening position of said valves; 
 a first cam follower for engagement with one of said cam lobes of said second camshaft for controlling the position of at least one of said first spring biased valves; and 
 a second cam follower engaged with at least one cam lobe of said second camshaft for imparting torsional input to said second camshaft, said second cam follower being biased by a contacting spring separate from said first spring biasing said valve.